The present invention relates to television cameras, and more particularly to television camera circuits for generating auxiliary signals, such as a signal for forming characters on the screen of the view finder of the camera, a vertical interval time code signal, a window signal for gating various video-related signals generated by the TV camera, etc.
The principal purpose of a television camera is, of course, to provide a color or black and white video signal representative of a scene being viewed by the camera. In the process of generating video signals, however, a television camera often generates a number of additional signals, all synchronized to the video signal being generated. It has, for example, been found desirable to record a time code signal along with the video signal to assist in the later editing of the recorded video. The two most popular time codes in the United States are the so-called SMPTE (Society of Motion Picture and Television Engineers) longitudinal time code (LTC) and vertical interval time code (VITC). Consequently, often a television camera will include circuitry for generating one or both of the two time codes to be recorded along with the video signal generated by the camera. Circuitry may also be included for providing an auxiliary signal which, when added together with the video signal being applied to the view finder associated with the camera, will result in the display of alphanumeric (A/N) information on the viewfinder screen. A camera may generate other auxiliary signals for gating the video signal or related signals to processing circuits for use in setting up the camera. It has conventionally been the practice to provide different circuitry for generating each different auxiliary signal.